In the present study, the effect of post-weld heat treatment on the soft zone of 1.25Cr-0.5Mo steel welded joint has been systematically studied. Outstanding features of the soft zone, including grain size, number density of carbides, volume fraction of carbides, and hardness distribution, are quantitatively analyzed by means of scanning electron microscopy and a microhardness testing. Results show that ferrite grain growth, carbide coarsening, and alloying element segregation are main factors accounting for hardness variations.

中文翻译：

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焊接后热处理过程中模拟1.25Cr-0.5Mo钢焊接接头中软区的演变

在本研究中，已经系统地研究了焊后热处理对1.25Cr-0.5Mo钢焊接接头软区的影响。通过扫描电子显微镜和显微硬度测试对软区的突出特征进行了定量分析，包括晶粒尺寸，碳化物的数量密度，碳化物的体积分数和硬度分布。结果表明，铁素体晶粒长大，碳化物粗化和合金元素偏析是造成硬度变化的主要因素。